1. Field of the Invention
The present invention relates to a semiconductor structure and a method for making the same, and more particularly to a semiconductor structure having a through via and a method for making the same.
2. Description of the Related Art
FIG. 1 shows a cross-sectional view of a conventional semiconductor structure. The conventional semiconductor structure 1 has a plurality of wafers 11 and an underfill 12. Each of the wafers 11 has a first surface 111, a second surface 112, a first redistribution layer (RDL) 113, a second redistribution layer (RDL) 114, a plurality of chips 117, a plurality of through vias 115 and a plurality of bumps 116. The first redistribution layer (RDL) 113 is disposed on the first surface 111. The second redistribution layer (RDL) 114 is disposed on the second surface 112. The chips 117 are disposed in the wafer 11, and exposed to the first surface 111 and the second surface 112. The through vias 115 are disposed in the chips 117, exposed to the first surface 111 and the second surface 112, and electrically connect the first redistribution layer (RDL) 113 and the second redistribution layer (RDL) 114. The bumps 116 are disposed on the second redistribution layer (RDL) 114, and electrically connected to the through vias 115. The underfill 12 is disposed between two adjacent wafers 11, and encapsulates the bumps 116, so as to connect the wafers 11.
The conventional semiconductor structure 1 has the following disadvantages. The conventional semiconductor structure 1 is formed by stacking the wafers 11. For electrically connecting the chips 117, the through vias 115 are formed in each chip 117, and then the first redistribution layer (RDL) 113, the second redistribution layer (RDL) 114 and the bumps 116 are formed in each wafer 11, which leads to a high manufacturing cost. Moreover, the pitch between the bumps 116 of the wafers 11 is narrowed to reduce the size of the product, so the underfill 12 is difficult to fill up the gap between the bumps 116 and encapsulate the bumps 116 when the wafers 11 are connected. Thus the yield rate of the product is reduced.
Therefore, it is necessary to provide a semiconductor structure and a method for making the same to solve the above problems.